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  <span class="target" id="memoryview-objects"></span><section id="index-0">
<span id="id1"></span><h1>MemoryView objects<a class="headerlink" href="#index-0" title="Permalink to this headline">¶</a></h1>
<p>A <a class="reference internal" href="../library/stdtypes.html#memoryview" title="memoryview"><code class="xref py py-class docutils literal notranslate"><span class="pre">memoryview</span></code></a> object exposes the C level <a class="reference internal" href="buffer.html#bufferobjects"><span class="std std-ref">buffer interface</span></a> as a Python object which can then be passed around like
any other object.</p>
<dl class="function">
<dt id="c.PyMemoryView_FromObject">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a> *<code class="sig-name descname">PyMemoryView_FromObject</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *obj</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_FromObject" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Create a memoryview object from an object that provides the buffer interface.
If <em>obj</em> supports writable buffer exports, the memoryview object will be
read/write, otherwise it may be either read-only or read/write at the
discretion of the exporter.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyMemoryView_FromMemory">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a> *<code class="sig-name descname">PyMemoryView_FromMemory</code><span class="sig-paren">(</span>char<em> *mem</em>, Py_ssize_t<em> size</em>, int<em> flags</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_FromMemory" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Create a memoryview object using <em>mem</em> as the underlying buffer.
<em>flags</em> can be one of <code class="xref c c-macro docutils literal notranslate"><span class="pre">PyBUF_READ</span></code> or <code class="xref c c-macro docutils literal notranslate"><span class="pre">PyBUF_WRITE</span></code>.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 3.3.</span></p>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyMemoryView_FromBuffer">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a> *<code class="sig-name descname">PyMemoryView_FromBuffer</code><span class="sig-paren">(</span><a class="reference internal" href="buffer.html#c.Py_buffer" title="Py_buffer">Py_buffer</a><em> *view</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_FromBuffer" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Create a memoryview object wrapping the given buffer structure <em>view</em>.
For simple byte buffers, <a class="reference internal" href="#c.PyMemoryView_FromMemory" title="PyMemoryView_FromMemory"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyMemoryView_FromMemory()</span></code></a> is the preferred
function.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyMemoryView_GetContiguous">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a> *<code class="sig-name descname">PyMemoryView_GetContiguous</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *obj</em>, int<em> buffertype</em>, char<em> order</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_GetContiguous" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Create a memoryview object to a <a class="reference internal" href="../glossary.html#term-contiguous"><span class="xref std std-term">contiguous</span></a> chunk of memory (in either
‘C’ or ‘F’ortran <em>order</em>) from an object that defines the buffer
interface. If memory is contiguous, the memoryview object points to the
original memory. Otherwise, a copy is made and the memoryview points to a
new bytes object.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyMemoryView_Check">
int <code class="sig-name descname">PyMemoryView_Check</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *obj</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_Check" title="Permalink to this definition">¶</a></dt>
<dd><p>Return true if the object <em>obj</em> is a memoryview object.  It is not
currently allowed to create subclasses of <a class="reference internal" href="../library/stdtypes.html#memoryview" title="memoryview"><code class="xref py py-class docutils literal notranslate"><span class="pre">memoryview</span></code></a>.  This
function always succeeds.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyMemoryView_GET_BUFFER">
<a class="reference internal" href="buffer.html#c.Py_buffer" title="Py_buffer">Py_buffer</a> *<code class="sig-name descname">PyMemoryView_GET_BUFFER</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *mview</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_GET_BUFFER" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a pointer to the memoryview’s private copy of the exporter’s buffer.
<em>mview</em> <strong>must</strong> be a memoryview instance; this macro doesn’t check its type,
you must do it yourself or you will risk crashes.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyMemoryView_GET_BASE">
<a class="reference internal" href="buffer.html#c.Py_buffer" title="Py_buffer">Py_buffer</a> *<code class="sig-name descname">PyMemoryView_GET_BASE</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *mview</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_GET_BASE" title="Permalink to this definition">¶</a></dt>
<dd><p>Return either a pointer to the exporting object that the memoryview is based
on or <code class="docutils literal notranslate"><span class="pre">NULL</span></code> if the memoryview has been created by one of the functions
<a class="reference internal" href="#c.PyMemoryView_FromMemory" title="PyMemoryView_FromMemory"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyMemoryView_FromMemory()</span></code></a> or <a class="reference internal" href="#c.PyMemoryView_FromBuffer" title="PyMemoryView_FromBuffer"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyMemoryView_FromBuffer()</span></code></a>.
<em>mview</em> <strong>must</strong> be a memoryview instance.</p>
</dd></dl>

</section>


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